a digital readout ticking down toward certain death - and a fate more
horrible still.

For Alan Rockaway, his teenaged son Jeff, and Alan's new bride, Jenny,
it's been little more than a fascinating tourist submarine excursion, a
leisurely end to a weeklong church-couples' cruise. Then the horrifying
crash and the plunge toward the unknown....

Everything Alan has assumed about himself, about what awaits him in the
future, is flipped upside down.